We just had tile installed and the flange is about 3/8" below the tile. I purchased one of those extra-thick wax rings with the rubber ring inside the wax. When I placed the wax ring on the toilet the ring extends about 1/2" or so below the bottom edge of the toilet. When I seated the toilet I did have to push down a little to get the toilet to seat, not a lot however. The guy at home depot told me to stack two. Wouldn't that have been too much wax? Stacking them would have extended the wax about 1" below the edge of the toilet bowl.